On 08/01/2026 12:35, Christophe Lyon wrote:
>
>
> On 1/8/26 12:53, Artemiy Volkov wrote:
>> The check_effective_target_arm_v8_3a_fp16_complex_neon_ok_nocache
>> procedure in target-supports.exp should return a set of flags providing
>> all of AdvSIMD, complex numbers, and fp16 capabilities. However, to
>> achieve this we have to be able to overwrite the current -mfpu setting.
>> This means that the current empty string alternative for $flags does not
>> work for us. This patch splits sets of options to iterate over
>> between the arm and the aarch64 backend and prohibits an empty string for
>> the former. Moreover, it changes
>> check_effective_target_arm_v8_3a_complex_neon_ok_nocache in the same way.
>>
>> This (fully) fixes the advsimd-intrinsics.exp/vector-complex_f16.c
>> testcase, which was previously being compiled with the -mfpu=neon-fp16
>> flag added by the .exp file itself.
>>
>> Tested on aarch64 by me and on arm by Christophe.
>>
>> Co-authored-by: Richard Earnshaw <[email protected]>
>>
>> gcc/testsuite/ChangeLog:
>>
>> * lib/target-supports.exp:
>> (check_effective_target_arm_v8_3a_complex_neon_ok_nocache):
>> Split and fill in arm and aarch64 compile options. Remove the
>> cpu_unset variable.
>> (check_effective_target_arm_v8_3a_fp16_complex_neon_ok_nocache):
>> Likewise.
>> ---
>> gcc/testsuite/lib/target-supports.exp | 31 +++++++++++++++++----------
>> 1 file changed, 20 insertions(+), 11 deletions(-)
>>
>> diff --git a/gcc/testsuite/lib/target-supports.exp
>> b/gcc/testsuite/lib/target-supports.exp
>> index dbcba42629f..210e246c955 100644
>> --- a/gcc/testsuite/lib/target-supports.exp
>> +++ b/gcc/testsuite/lib/target-supports.exp
>> @@ -13717,27 +13717,32 @@ proc check_effective_target_inff { } {
>> proc check_effective_target_arm_v8_3a_complex_neon_ok_nocache { } {
>> global et_arm_v8_3a_complex_neon_flags
>> set et_arm_v8_3a_complex_neon_flags ""
>> - set cpu_unset ""
>> if { ![istarget arm*-*-*] && ![istarget aarch64*-*-*] } {
>> return 0;
>> }
>> if { [istarget arm*-*-*] } {
>> - set cpu_unset "-mcpu=unset"
>> + set flag_opts {
We should try "" first, before attempting to modify the architecture.
>> + "-mcpu=unset -mfpu=auto -march=armv8.3-a+simd"
>> + "-mcpu=unset -mfloat-abi=softfp -mfpu=auto -march=armv8.3-a+simd"
>> + "-mcpu=unset -mfloat-abi=hard -mfpu=auto -march=armv8.3-a+simd"
>> + }
>> + } else {
>> + set flag_opts { "" "-march=armv8.3-a" }
>> }
>
> While this had no visible effect with the configurations I/we have tested, I
> suspect we still want to start with just "-mcpu=unset" on arm. Richard?
We only want to add -mcpu=unset if we're overriding the defaults. And since we
should try "" before trying anything else, it has to be part of the options
where this is needed.
AFAIK aarch64 doesn't support -mcpu=unset (yet), so it's correct not to add
that for the aarch64 list.
>
> And on aarch64, dropping +simd seems harmless at the moment, but maybe we
> want to keep it in order to be more future-proof?
I'll let Tamar make the call on that one. But as things stand we always
default to having simd on aarch64 and I expect there will be a huge amount of
testsuite churn if that ever changes, so I'm not too worried about that.
>
> Thanks,
>
> Christophe
>
>> # Iterate through sets of options to find the compiler flags that
>> # need to be added to the -march option.
>> - foreach flags {"" "-mfloat-abi=softfp -mfpu=auto" "-mfloat-abi=hard
>> -mfpu=auto"} {
>> + foreach flags $flag_opts {
>> if { [check_no_compiler_messages_nocache \
>> arm_v8_3a_complex_neon_ok assembly {
>> #if !defined (__ARM_FEATURE_COMPLEX)
>> #error "__ARM_FEATURE_COMPLEX not defined"
>> #endif
>> #include <complex.h>
>> - } "$flags $cpu_unset -march=armv8.3-a+simd"] } {
>> - set et_arm_v8_3a_complex_neon_flags "$flags $cpu_unset
>> -march=armv8.3-a+simd"
>> + } "$flags"] } {
>> + set et_arm_v8_3a_complex_neon_flags "$flags"
>> return 1;
>> }
>> }
>> @@ -13765,19 +13770,24 @@ proc add_options_for_arm_v8_3a_complex_neon {
>> flags } {
>> proc check_effective_target_arm_v8_3a_fp16_complex_neon_ok_nocache { } {
>> global et_arm_v8_3a_fp16_complex_neon_flags
>> set et_arm_v8_3a_fp16_complex_neon_flags ""
>> - set cpu_unset ""
>> if { ![istarget arm*-*-*] && ![istarget aarch64*-*-*] } {
>> return 0;
>> }
>> if { [istarget arm*-*-*] } {
>> - set cpu_unset "-mcpu=unset"
>> + set flag_opts {
Same here, add "" first.
>> + "-mcpu=unset -mfpu=auto -march=armv8.3-a+fp16+simd"
>> + "-mcpu=unset -mfloat-abi=softfp -mfpu=auto
>> -march=armv8.3-a+fp16+simd"
>> + "-mcpu=unset -mfloat-abi=hard -mfpu=auto -march=armv8.3-a+fp16+simd"
>> + }
>> + } else {
>> + set flag_opts { "" "-march=armv8.3-a+fp16" }
>> }
>> # Iterate through sets of options to find the compiler flags that
>> # need to be added to the -march option.
>> - foreach flags {"" "-mfloat-abi=softfp -mfpu=auto" "-mfloat-abi=hard
>> -mfpu=auto"} {
>> + foreach flags $flag_opts {
>> if { [check_no_compiler_messages_nocache \
>> arm_v8_3a_fp16_complex_neon_ok assembly {
>> #if !defined (__ARM_FEATURE_COMPLEX)
>> @@ -13787,9 +13797,8 @@ proc
>> check_effective_target_arm_v8_3a_fp16_complex_neon_ok_nocache { } {
>> #error "__ARM_FEATURE_FP16_VECTOR_ARITHMETIC not defined"
>> #endif
>> #include <complex.h>
>> - } "$flags $cpu_unset -march=armv8.3-a+fp16+simd"] } {
>> - set et_arm_v8_3a_fp16_complex_neon_flags \
>> - "$flags $cpu_unset -march=armv8.3-a+fp16+simd"
>> + } "$flags"] } {
>> + set et_arm_v8_3a_fp16_complex_neon_flags "$flags"
>> return 1;
>> }
>> }
>
R.
